The big topic surrounding Aggies football following the 2014 season wasn’t the team’s 8-5 record, or even the win over West Virginia in the Liberty Bowl. It was how the team could improve their defense, which had been under constant scrutiny since the start of the Kevin Sumlin era.

It didn’t take long for Sumlin to address the issue, replacing defensive coordinator Mark Snyder with former LSU coordinator John Chavis, whose hard-nosed approach served him well in his six seasons with the Tigers and 20 seasons with Tennessee before that.

Ball State, the Aggies’ next opponent, had similar questions coming into 2015. Even after a win over VMI to open the season, questions about the Cardinal defense still remain.

Let’s examine how each team addressed its defensive liabilities from last season to now:

Texas A&M Aggies

What went wrong: The Aggies had problems creating turnovers for the offense last season. They averaged only one per game, and had just three multiple-turnover games.

Sacks were also in rare supply, with the Aggies getting to the opposing quarterback an average of just 2.8 times per game. Their output on tackles for loss was just 5.8, and they allowed more than 450 yards and 28 points per contest.

Signs of improvement: It’s only been one game, but Chavis has already made an impact. In the season-opening 38-17 win over No. 15 Arizona State, the Aggies defense greatly improved on last year’s totals, forcing two turnovers, 14 tackles for loss and nine sacks. It was the biggest sack total since 1995, when they had 10 against Texas Tech.

The Sun Devils managed just 92 total rushing yards and 247 through the air. While Chavis has reason to be proud of his unit’s performance against a ranked opponent, especially in a season opener, he understands a lot of work remains to be done.

“It’s one game,” he told reporters following the victory. “All we’ve done is win one game, and that’s not what we’ve worked all summer for.”

Maybe not, but Aggie fans are hoping this is the start of better days on the defensive side of the ball.

Ball State Cardinals

What went wrong: What a difference a year makes. In 2013, Ball State coach Pete Lembo led his team to a 10-2 record, then lost 23-20 to Arkansas State in the GoDaddy Bowl.

Last season, Lembo’s fourth with the Cardinals, was a major step backward. They finished 5-7, due in large part to a weak defense that ranked 112th in the nation. They gave up numerous big plays, and were 116th in sacks.

In this season’s opening win against Virginia Military Institute, the Cardinals built up a 24-point lead before allowing VMI to pull to within 10 in the fourth quarter. The Cardinals escaped with a 48-36 win, but the defense still appeared undisciplined, giving up back-to-back plays of at least 30 yards in the third quarter.

Signs of improvement: The Cardinals return six of their front seven from last season (although some fans might argue that’s not such a good thing). Lembo is hoping seniors Michael Ayers and Darnell Smith will be better, as they combined for a total of just six sacks between them. 2013 second-team All-MAC selection Ben Ingle, who made 87 tackles last season, is back. So is Zack Ryan, who recovered two fumbles in 2014 to go with 91 tackles.

“A ton to fix, but hopefully things that are fixable,” Lembo said of his defense following the VMI win.

The Cardinals have the misfortune of playing in the high-scoring MAC West Division, so they’ll need better numbers than that if they hope to get back to a bowl game.